Temperature measurement sites

Core temperature is considered to be the temperature of blood perfusing the vital organs such as the heart and brain. Small temperature gradients exist between different parts of the body. For example 95% of all young adults would be expected to have a morning oral temperature of 36.3-37.1°C, whereas the temperature of the scrotum is carefully regulated at 32°C. Therefore the ability of measured value to reflect core temperature depends on the site chosen.

The following sites may be used:

Adult skin temperature sensor

Temporal artery thermometry

Tympanic membrane

Nasopharynx

Oesophagus

Blood

Bladder

Rectum

Adult skin temperature sensor

The Adult Skin Temperature Sensor can be used in all clinical settings requiring routine monitoring surface temperature.

The Exergen Temporal Scanner provides a totally non-invasive, quick, easy and reproducible method of core temperature measurement. By gently stroking the Temporal Scanner across the forehead, it will provide a reading in approximately 3 seconds without the discomfort associated with oral, rectal, or tympanic thermometers.

Tympanic membrane

Tympanic membrane temperature accurately mirrors oesophageal temperature and is a good indicator of core and brain temperature. Infrared tympanic thermometers (ITT's) measure the frequency of infrared light emitted by the tympanic membrane. The operator needs to ensure that the external auditory canal is free from wax prior to use and the instrument used cautiously as perforation of the tympanic membrane has been described.

The Tympanic Temperature Probe is designed for atraumatic measurement of patient temperature from the aural canal.

Contoured ear piece ensures simple, secure placement

Soft cotton tip to minimise trauma

Sturdy wire connector assemblies are engineered for dependability

Extra long lead eliminates wire tension

Nasopharynx

The temperature probe gives a fairly accurate measurement of core temperature and should be positioned just behind the soft palate. Incorrect placement leads to inaccurate results due to the cooling effects of inspired gasses. It is a less accurate measure of core temperature when compared with the oesophageal probe.

Oesophagus

The probe is most accurate in the lower 25% of the oesophagus. When correctly placed it provides a good estimate of cardiac temperature. These probes lose their accuracy during thoracotomy, due to local cooling effects of tissues.

The Oesophageal Stethoscope with temperature sensor is designed for use in surgical settings to monitor heart and respiratory sounds and to measure core body temperature of anaesthetised patients.

Provides outstanding heart and respiratory sound transmission

Available with and without temperature monitoring capability

Fully compatible with most monitors

Available in both regular and soft flexibility for enhanced patient comfort

Atraumatic, low friction surface for ease of insertion

Complete line includes all popular French sizes

Blood

Blood temperature can be measured using a thermistor attached to a pulmonary flotation catheter (Schwan-Ganzcatheter). Measuring blood temperature in the pulmonary circulation is the best estimate of core temperature but this is a very invasive technique. It can also be used to measure cardiac output using thermodilution.

The Foley Catheter with temperature sensor is used for urinary drainage and simultaneous monitoring of bladder temperature.

Dual-purpose design can be used before, during and after surgery

Colour coded hubs for precise size identification

Positive locking connector for secure cable attachment

Fully compatible with most monitors

Safe, non-toxic components

Complete range of sizes: 8-18 French

Dependable silicone construction

Rectum

Rectal temperature is influenced by the cooling effect of blood returning from the lower limbs and the heat generated by the thermogenic gut flora. The insulating effect of faeces results in rectal temperature being 0.5-1.0°C higher than core temperature and compared with other sites, response time is slow.